Trade: Chicago White Sox vs. Seattle Mariners
Resolution criteria on PolyGram: In the upcoming MLB game between the Chicago White Sox and Seattle Mariners, scheduled for May 18 at 9:40PM ET: This market will resolve to "Chicago White Sox" if the Chicago White Sox win the game. This market will resolve to "Seattle Mariners" if the Seattle Mariners win the game. If the game is postponed, this market will remain open until the game has been completed. If the game is canceled entirely, with no make-up game, or ends in a tie, this market will resolve 50-50. The primary resolution source for this market is the official final statistics of the event as recognized by the governing body or event organizers.
PolyGram is an on-chain prediction market where you trade YES or NO outcome shares with real USDC on Polygon. For this market, buy YES if you believe the event will happen, or NO if you think it won't. Your maximum loss is your stake — winning shares pay $1.00 each at resolution. Unlike sportsbooks, there is no house edge: prices are set by supply and demand from other traders and reflect the crowd's real-time probability.
- Liquidity
- $18K
- Total Volume
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- 24h Volume
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- Open Interest
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Market outcomes
| Chicago White Sox vs. Seattle Mariners | 35% YES | 66% NO |
| NRFI | 51% YES | 49% NO |
Market context
The Chicago White Sox travel to Seattle to face the Mariners on 18 May at 9:40PM ET, with the market currently pricing a White Sox victory at 34 per cent on Polymarket's order book. This implies roughly 66 per cent probability assigned to a Mariners win, reflecting Seattle's stronger regular-season positioning heading into late May. The settlement window extends to 26 May, allowing for fixture postponements common in MLB's Pacific Northwest schedule.
Historical matchups between these franchises show the Mariners have held marginal advantages in recent seasons, though individual game outcomes remain volatile. The White Sox entered 2026 as a rebuilding outfit with inconsistent performance, whilst Seattle has maintained competitive rosters. The current 34 per cent probability for Chicago aligns with typical market pricing for the weaker team in such fixtures, though this reflects aggregate expectation rather than specific pitching matchups or roster availability on the day.
Traders should monitor starting pitcher announcements, which typically materialise 24–48 hours before first pitch and materially shift game probabilities. Recent injury reports and roster moves will influence the order book's depth. Weather conditions at T-Mobile Park—notably wind direction affecting fly ball distances—represent a secondary catalyst. The Mariners' home-field advantage in Seattle's cooler May climate historically favours their pitching-heavy approach, a factor already partially reflected in the current odds but subject to revision as game-day specifics emerge.
Wikipedia Context
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Chicago White SoxThe Chicago White Sox are an American professional baseball team based in Chicago. The White Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) Central Division. The club plays its home games at Rate Field, which is located on Chicago's South Side. They are one of two MLB teams based in Chicago, alongside the National Lea
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Chicago White Sox minor league players
Below is a partial list of minor league baseball players in the Chicago White Sox organizations and rosters of their affiliates:
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Chicago White Sox all-time roster
The following is a list of players and managers (*), both past and current, who appeared at least in one regular season game for the Chicago White Sox franchise.
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Chicago White Sox Radio Network
The Chicago White Sox Radio Network is an American radio network airing baseball games from the Chicago White Sox. The English-language flagship is WMVP in Chicago, with Spanish language coverage airing on WRTO (1200). The English language network consists of 19 stations For the 2019 season, the play-by-play announcers were Ed Farmer and Jason Benetti ; the
Resolution source
This market settles from the official outcome published at https://www.mlb.com/. A proposer submits the final result to the UMA optimistic oracle on Polygon; the two-hour dispute window closes and payouts clear in USDC.
How to trade this market step by step
The mechanics for trading "Chicago White Sox vs. Seattle Mariners" are the same as any other PolyGram sporting event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.
- Sign in on polygram.ink with your email — no full KYC under $1,500 lifetime trading volume.
- Deposit USDC on Polygon (lowest fees, ~$0.01 per transaction) or Ethereum. Funds credit after 12 confirmations.
- Pick a side. Buy YES if you believe the event will happen; buy NO if you think it won't. The current YES price reflects the market's collective probability.
- Size your position. If you stake 100 USDC at 50% YES, you'll receive shares that pay $200 if YES resolves true — a 100% gross return. If NO resolves, your shares are worth $0.
- Set risk controls (optional). Stop-loss, take-profit, and limit-order types all supported. Use the trade ticket's slippage box to cap your maximum entry price.
- Wait for resolution. When the event resolves on-chain via the UMA optimistic oracle, the winning side settles to 100¢ automatically and USDC hits your balance within seconds. Withdrawable to any wallet you control.
How active is this market?
$0 in lifetime turnover and $18K of resting liquidity puts this market in the below the median by volume for sports contracts on PolyGram. Order-book depth is modest — expect a couple of cents of slippage on $1k+ trades.
The market has been open for under a month — fresh enough that information asymmetry remains a real factor.
Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.
Key terms
- YES / NO share
- A binary outcome token that pays $1.00 if the underlying claim resolves true (YES) or false (NO), and $0 otherwise. The market price between 0¢ and 100¢ is the implied probability.
- CLOB
- Central limit order book. The matching engine that pairs YES buyers with NO buyers (effectively the same trade). Polymarket's CLOB on Polygon executes trades on-chain via the conditional-tokens framework.
- Liquidity
- USDC capital sitting in resting limit orders inside the order book. Deeper liquidity means smaller slippage on large trades and a tighter bid-ask spread.
- UMA optimistic oracle
- The on-chain dispute system that settles each Polymarket market. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution.
- Slippage
- The difference between the displayed mid-price and your fill price. Affects market orders most; limit orders avoid slippage but may take time to fill.
- Conditional token
- ERC-1155 outcome share issued by Gnosis Conditional Tokens on Polygon. The token type that resolves to $1.00 or $0.00 at settlement.
Frequently asked questions
How does this market resolve?
Resolution is sourced from https://www.mlb.com/. Settlement is executed by the UMA optimistic oracle on Polygon, with a 2-hour dispute window before payouts clear.
When does this market close?
This prediction market is scheduled to close on 26 May 2026. After the resolving event occurs, settlement typically clears within 24 hours once the UMA optimistic oracle confirms the outcome. All payouts are in USDC on the Polygon network.
How can I trade on "Chicago White Sox vs. Seattle Mariners"?
To trade on this prediction market, create a free PolyGram account at polygram.ink, deposit USDC via Polygon, and place a YES or NO order on the outcome you believe in. You can learn more on our how-it-works page. Your maximum loss is limited to your stake — there is no leverage or margin.
What happens when the market resolves?
When the outcome is determined, winning YES shares pay out $1.00 each in USDC, while losing shares pay $0. Settlement is handled by the UMA optimistic oracle on Polygon — a proposer submits the result, a two-hour dispute window opens, and if uncontested, payouts are distributed automatically. You can withdraw your winnings to any Polygon wallet.
Risk and regulatory note
Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.
Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.
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